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V1 and v2b interneurons secure the alternating flexor-extensor motor activity mice require for limbed locomotion.

ABSTRACT: Reciprocal activation of flexor and extensor muscles constitutes the fundamental mechanism that tetrapod vertebrates use for locomotion and limb-driven reflex behaviors. This aspect of motor coordination is controlled by inhibitory neurons in the spinal cord; however, the identity of the spinal interneurons that serve this function is not known. Here, we show that the production of an alternating flexor-extensor motor rhythm depends on the composite activities of two classes of ventrally located inhibitory neurons, V1 and V2b interneurons (INs). Abrogating V1 and V2b IN-derived neurotransmission in the isolated spinal cord results in a synchronous pattern of L2 flexor-related and L5 extensor-related locomotor activity. Mice lacking V1 and V2b inhibition are unable to articulate their limb joints and display marked deficits in limb-driven reflex movements. Taken together, these findings identify V1- and V2b-derived neurons as the core interneuronal components of the limb central pattern generator (CPG) that coordinate flexor-extensor motor activity.

SUBMITTER: Zhang J

PROVIDER: S-EPMC4096991 | biostudies-other | 2014 Apr

REPOSITORIES: biostudies-other

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V1 and v2b interneurons secure the alternating flexor-extensor motor activity mice require for limbed locomotion.

Zhang Jingming J Lanuza Guillermo M GM Britz Olivier O Wang Zhi Z Siembab Valerie C VC Zhang Ying Y Velasquez Tomoko T Alvarez Francisco J FJ Frank Eric E Goulding Martyn M

Neuron 20140401 1

Reciprocal activation of flexor and extensor muscles constitutes the fundamental mechanism that tetrapod vertebrates use for locomotion and limb-driven reflex behaviors. This aspect of motor coordination is controlled by inhibitory neurons in the spinal cord; however, the identity of the spinal interneurons that serve this function is not known. Here, we show that the production of an alternating flexor-extensor motor rhythm depends on the composite activities of two classes of ventrally located ...[more]

PMID: 24698273

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Dataset Information

V1 and v2b interneurons secure the alternating flexor-extensor motor activity mice require for limbed locomotion.

Publications

V1 and v2b interneurons secure the alternating flexor-extensor motor activity mice require for limbed locomotion.

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